NZ-USA Voltage Converter Wiring Diagram or Schematic

Go down to Dick Smith's and buy a 240-110V step-down transformer. They have various sizes, so you could buy one just big enough for one device or you could even buy one big enough for the lot and run an outlet board of it.

Ken

Thanks Ken, I will try that as soon as I get to Dick Smiths.

This sounds almost too simple and I hope it works.

1. Have you had any experience with doing same in anyway that you could offer additional advice?

1. Any thoughts as to why the Radio Shack unit was suppling only 88VAC?

With much appreciation.

Bob

My guess is that RS uses a tiny transfomer that has crappy voltage regulation. What's the voltage, with, and without a load?

The DSE transformer approach will work fine, but it may become expensive, or one transformer may a PITA running 110vac leads and outlet strips from room to room.

I have a lot of USA-sourced power tools and have the woodwork shop fitted out with a BIG transformer and several outlet strips, but it would be a real PITA in more than one room.

A more convenient alternative may be to use some cheap NZ 230vac "Wall-warts" to provide the 9, or 12, or whatever, voltage to the end unit.

When we decommissioned one of our US facilities we brought back truck-loads of gear, some of which was 110VAC only, so yes, been there, done that! Also done this at home - at home I tend to just power units individually from a small (but adequate!) step-down transformer. At work we ended up putting in a mother-of-all-step-down transformers and did a proper distribution. Unless you had tons of equipment to power, this is probably not the way to go at home.

As Barry says, the RS unit probably didn't have the 'oomph' to supply whatever it was you were using. As he says, check whether you can just buy a new power-pack (wall-wart) which runs off 240VAC, or even check whether your gear can be switched to 240V, or it may even be 'universal'.

Incidentally, prices are so cheap in NZ these days (for consumer gear) that in many cases I wouldn't have thought that the freight was worthwhile. If you still need to truck your gear over here, check first.

Cheers.

Ken

Ah, the joys of paying indonesions $0.35 per month.

most of its crap though.

Cheers Terry

As others noted, NZ prices (for crap) have come down a lot in the past few years, so do a check before you leave. We do have a large chain here (The Warehouse) that sells asian stuff very cheaply. It's a bit like a cross between Walmart and "The Christmas Tree Shop" (In New England, don't know if they are where you are) but not as neatly laid out. They do have toasters, irons, etc for $12-$20, all made where english is a second language! Good quality stuff (like Porter Cable or DeWalt power tools) are still much cheaper in the US.

Barry

Amazingly, they're made in the US too. I much like Porter Cable tools, BTW.

Ken, Barry, Terry & Keith,

Thanks for your input and advice; it's worth while to me.

Comments and answers to questions:

1. The RS 88vac is a no-load state, and goes down as I add devices to a US-power-strip I'm using;
2. Since my daughter/son-in-law will only be in current house several months, I dont want to do the distribution idea;
3. My daughter received gifts fron US family and friends that dont understand power differences and my wife didn't want to hurt feelings...;
4. The devices I have are baby monitors, Digital equipment charges, and the like.

In closing, isn't there a simiconductor like varistor that could be used for my purpose?

Bob

Urk!

Good idea.

:-) I have a sister currently in Salt Lake City who is grappling with the concept that she can't (easily) bring all these nice cheap goodies back home!

No. Basically, it's a transformer or nothing. Replacing wall-warts is a very good idea if possible, but otherwise you may be out of luck with an alternative.

Cheers.

Ken

or a universal (80-265Vac) input 115Vac inverter ($$$).

Cheers Terry

PS I've got a 1kVA step-down xfmr to run the things I brought back from Boston.

We got a 10kVA transformer made here in Auckland, and we've done a full distribution, but this is commercial so that's a little different. :-) The universal converter is a good idea "in theory" but as you say, $$$, plus OP doesn't want to wire a 110V distribution, which is pretty sane thinking IMHO.

I think he's stuck with small transformer(s).

Cheers.

Ken

Hi Bob Searching the Radio Shack website on the cat # you gave previously shows that your device is supposed to be capable of 1000W for one hour, 1600W for 15 mins. Irrespective of the 88V output, the devices you list below are all low power and wouldn't be expected to cause a stepdown transformer output voltage to noticably fall.

However, that cat# doesn't seem to still be available. Searching on travel converters gives a range that includes another 1600W unit cat #

"Operates 120VAC heating devices from 240VAC For irons, lamps, handheld hair dryers Range 50-1600 watts. Not recommended for products under 50 watts"

Looking at the picture of it shows a device that is quite small compared to a transformer based unit of that wattage. How big and heavy is your unit?

My guess is that your Radio Shack unit is a phase control unit (Triac or SCR) that is not going to work for your use. This would also explain the 88V reading your meter is giving.

As others have suggested, go and visit DSE or Jaycar.

That's what I think you already have and it doesn't work for other than resistive loads. We could also have a discussion about the safety implications of your device :-)

-- Regards Malcolm Remove sharp objects to get a valid e-mail address

Ken, Terry,

Again, thanks for your input.

Malcolm,

The RS unit I have is rather small, (2x2x4) so, as you suggest, it is the Triac/SCR version (I knew there was a semiconductor unit) and I guess it can't handle the load of a laptop I brought over and was thinking of giving to my daughter. The unit overheats because it gives off an over-heating ordor.

I have tried Dick Smiths and they don't have what I need and the prices are way too much because they were user freirndly finished products. He look for a "bare" stepdown and couldn't find one in the 500-10000ma range which is what I feel is what I need. I also asked the DS sales person if he could recommend another supplier of "bare" stepdowns but he didn't know of any. He suggested I try Net. Anyone know of supplier of stepdowns in Christchurst or NZ that I could have mailed to me that would be "reasonable." The DS salesperson did't know of the Wall-Wart units. Again, "cheap" is what I want but probably asking for "too much."

As usual, you guys and the NewsGroups are great and I always get great input.

With MUCH appreciation.

Bob

PS: I will try JayCar next, probably should have before this reply...

Ken, Terry,

Again, thanks for your input.

Malcolm,

The RS unit I have is rather small, (2x2x4) so, as you suggest, it is the Triac/SCR version (I knew there was a semiconductor unit) and I guess it can't handle the load of a laptop I brought over and was thinking of giving to my daughter. The unit overheats because it gives off an over-heating ordor.

I have tried Dick Smiths and they don't have what I need and the prices are way too much because they were user freirndly finished products. He look for a "bare" stepdown and couldn't find one in the 500-10000ma range which is what I feel is what I need. I also asked the DS sales person if he could recommend another supplier of "bare" stepdowns but he didn't know of any. He suggested I try Net. Anyone know of supplier of stepdowns in Christchurst or NZ that I could have mailed to me that would be "reasonable." The DS salesperson did't know of the Wall-Wart units. Again, "cheap" is what I want but probably asking for "too much."

As usual, you guys and the NewsGroups are great and I always get great input.

With MUCH appreciation.

Bob

PS: I will try JayCar next, probably should have before this reply...

Bob,

How many do you need? and are you in Christchurch? It looks like you only need some wall-warts for a few months, right? If so, I can raid my surplus box and maybe find a few that would suit and you could borrow. I'm about 30 mins out of ChCh.

Barry

Hi, I presume the current above is a typo and you meant

For bare transformers check

Don't forget to cost in freight & a box & plug & socket etc.

If you have access to someones junk box you could do the equivalent with two transformers if you can find two suitable units. One with

e.g. 230V > 24V > 24V > 120V

Have you checked that the laptop needs 120V? Many have universal supplies that handle anything between 100V - 250V.

-- Regards Malcolm Remove sharp objects to get a valid e-mail address

Malcolm, Barry, Terry and Ken,

My issue seems resolved... TBD

My daughter took me to a flea market where I was able to get four NZ (5vdc - 9vdc) chargers and a rather large 115->230 step-up transformer. I rewired the step-up for stepdown and it looks like it will work for my needs. The five items cost me $20 NZD; such a bargin. We all have to remember to include those flea markets in our problem solving situations...

I really want to thank all of you again for your input, advice, links, and offer of equipment loans (Barry, yes I'm in CHC).

Bob

PS: Returning to USA/PA next week and still have lots of non-electrical projects to complete before then.

Several companies have large toroids with two bifilar windings intended as the primary for 110 or 220 use prewound for the final user to put his own secondaries on. They can be used as autoformers to give

If a wall wart is involved, it is always better to get a new wall wart for the local voltage.